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The Study on the Effects of Technology Orientation and Market Orientation on Managerial Performance in Innopolis Start-ups: Focusing on the Moderating Effects of Marketing and R&D Expenses (연구소기업의 기술지향성과 시장지향성이 경영성과에 미치는영향: 마케팅 및 연구개발 비용의 조절효과를 중심으로)

  • Kwon, Haram;Yang, Young Seok
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.19 no.1
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    • pp.119-133
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    • 2024
  • As a result of significant investments by the government in promoting public technology commercialization and fostering a venture startup ecosystem, there have been quantitative achievements, such as the registration of over 1,600 Innopolis Start-ups since 2006, generating a total revenue of 1.1 trillion won as of 2021. However, these achievements have been overshadowed by critical qualitative challenges, including a continuous decline in average revenue per Innopolis Start-up. This led to a focus on whether managers' technological and market orientations affect business performance. This study aims to provide insights into improving the qualitative growth of Innopolis Start-ups by analyzing the effects of technological and market orientations on business performance, as well as the moderating effects of adjusting marketing and research and development (R&D) costs on this relationship. Through prior research and empirical analysis, this study derives three main findings. First, technological excellence and innovation significantly influence the business performance of Innopolis Start-ups, while technological intensity does not. Second, customer orientation and competitive orientation significantly impact business performance, whereas entry barriers as a single factor do not. Third, adjusting marketing and R&D costs, as controlled variables obtained through general situations, has no direct impact on other variables. However, it interacts with entry barriers, influencing financial business performance, with R&D costs exhibiting a negative buffering effect and marketing costs showing a positive enhancing effect. This study confirms that both technological and market orientations directly influence the business performance of Innopolis Start-ups, thus being crucial factors affecting their growth. Moreover, it establishes that investments in marketing and R&D play significant roles in alleviating initial entry barriers and enhancing financial performance. Consequently, it underscores the importance of reinforcing technological and market orientations tailored to the characteristics of Innopolis Start-ups. Additionally, it proposes five theoretical contributions: strengthening institutional support systems for technology commercialization and innovation, improving qualitative evaluation criteria during the selection process of Innopolis Start-ups, conducting comprehensive analyses of technological and market aspects during startup selection, enhancing support for marketing education and consulting for smooth market entry, and supporting expenditure strategies and milestone setting tailored to the industrial characteristics of individual Innopolis Start-ups.

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A Study on the Determinants of Patent Citation Relationships among Companies : MR-QAP Analysis (기업 간 특허인용 관계 결정요인에 관한 연구 : MR-QAP분석)

  • Park, Jun Hyung;Kwahk, Kee-Young;Han, Heejun;Kim, Yunjeong
    • Journal of Intelligence and Information Systems
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    • v.19 no.4
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    • pp.21-37
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    • 2013
  • Recently, as the advent of the knowledge-based society, there are more people getting interested in the intellectual property. Especially, the ICT companies leading the high-tech industry are working hard to strive for systematic management of intellectual property. As we know, the patent information represents the intellectual capital of the company. Also now the quantitative analysis on the continuously accumulated patent information becomes possible. The analysis at various levels becomes also possible by utilizing the patent information, ranging from the patent level to the enterprise level, industrial level and country level. Through the patent information, we can identify the technology status and analyze the impact of the performance. We are also able to find out the flow of the knowledge through the network analysis. By that, we can not only identify the changes in technology, but also predict the direction of the future research. In the field using the network analysis there are two important analyses which utilize the patent citation information; citation indicator analysis utilizing the frequency of the citation and network analysis based on the citation relationships. Furthermore, this study analyzes whether there are any impacts between the size of the company and patent citation relationships. 74 S&P 500 registered companies that provide IT and communication services are selected for this study. In order to determine the relationship of patent citation between the companies, the patent citation in 2009 and 2010 is collected and sociomatrices which show the patent citation relationship between the companies are created. In addition, the companies' total assets are collected as an index of company size. The distance between companies is defined as the absolute value of the difference between the total assets. And simple differences are considered to be described as the hierarchy of the company. The QAP Correlation analysis and MR-QAP analysis is carried out by using the distance and hierarchy between companies, and also the sociomatrices that shows the patent citation in 2009 and 2010. Through the result of QAP Correlation analysis, the patent citation relationship between companies in the 2009's company's patent citation network and the 2010's company's patent citation network shows the highest correlation. In addition, positive correlation is shown in the patent citation relationships between companies and the distance between companies. This is because the patent citation relationship is increased when there is a difference of size between companies. Not only that, negative correlation is found through the analysis using the patent citation relationship between companies and the hierarchy between companies. Relatively it is indicated that there is a high evaluation about the patent of the higher tier companies influenced toward the lower tier companies. MR-QAP analysis is carried out as follow. The sociomatrix that is generated by using the year 2010 patent citation relationship is used as the dependent variable. Additionally the 2009's company's patent citation network and the distance and hierarchy networks between the companies are used as the independent variables. This study performed MR-QAP analysis to find the main factors influencing the patent citation relationship between the companies in 2010. The analysis results show that all independent variables have positively influenced the 2010's patent citation relationship between the companies. In particular, the 2009's patent citation relationship between the companies has the most significant impact on the 2010's, which means that there is consecutiveness regarding the patent citation relationships. Through the result of QAP correlation analysis and MR-QAP analysis, the patent citation relationship between companies is affected by the size of the companies. But the most significant impact is the patent citation relationships that had been done in the past. The reason why we need to maintain the patent citation relationship between companies is it might be important in the use of strategic aspect of the companies to look into relationships to share intellectual property between each other, also seen as an important auxiliary of the partner companies to cooperate with.

An Empirical Study on Motivation Factors and Reward Structure for User's Createve Contents Generation: Focusing on the Mediating Effect of Commitment (창의적인 UCC 제작에 영향을 미치는 동기 및 보상 체계에 대한 연구: 몰입에 매개 효과를 중심으로)

  • Kim, Jin-Woo;Yang, Seung-Hwa;Lim, Seong-Taek;Lee, In-Seong
    • Asia pacific journal of information systems
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    • v.20 no.1
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    • pp.141-170
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    • 2010
  • User created content (UCC) is created and shared by common users on line. From the user's perspective, the increase of UCCs has led to an expansion of alternative means of communications, while from the business perspective UCCs have formed an environment in which an abundant amount of new contents can be produced. Despite outward quantitative growth, however, many aspects of UCCs do not meet the expectations of general users in terms of quality, and this can be observed through pirated contents and user-copied contents. The purpose of this research is to investigate effective methods for fostering production of creative user-generated content. This study proposes two core elements, namely, reward and motivation, which are believed to enhance content creativity as well as the mediating factor and users' committement, which will be effective for bridging the increasing motivation and content creativity. Based on this perspective, this research takes an in-depth look at issues related to constructing the dimensions of reward and motivation in UCC services for creative content product, which are identified in three phases. First, three dimensions of rewards have been proposed: task dimension, social dimension, and organizational dimention. The task dimension rewards are related to the inherent characteristics of a task such as writing blog articles and pasting photos. Four concrete ways of providing task-related rewards in UCC environments are suggested in this study, which include skill variety, task significance, task identity, and autonomy. The social dimensioni rewards are related to the connected relationships among users. The organizational dimension consists of monetary payoff and recognition from others. Second, the two types of motivations are suggested to be affected by the diverse rewards schemes: intrinsic motivation and extrinsic motivation. Intrinsic motivation occurs when people create new UCC contents for its' own sake, whereas extrinsic motivation occurs when people create new contents for other purposes such as fame and money. Third, commitments are suggested to work as important mediating variables between motivation and content creativity. We believe commitments are especially important in online environments because they have been found to exert stronger impacts on the Internet users than other relevant factors do. Two types of commitments are suggested in this study: emotional commitment and continuity commitment. Finally, content creativity is proposed as the final dependent variable in this study. We provide a systematic method to measure the creativity of UCC content based on the prior studies in creativity measurement. The method includes expert evaluation of blog pages posted by the Internet users. In order to test the theoretical model of our study, 133 active blog users were recruited to participate in a group discussion as well as a survey. They were asked to fill out a questionnaire on their commitment, motivation and rewards of creating UCC contents. At the same time, their creativity was measured by independent experts using Torrance Tests of Creative Thinking. Finally, two independent users visited the study participants' blog pages and evaluated their content creativity using the Creative Products Semantic Scale. All the data were compiled and analyzed through structural equation modeling. We first conducted a confirmatory factor analysis to validate the measurement model of our research. It was found that measures used in our study satisfied the requirement of reliability, convergent validity as well as discriminant validity. Given the fact that our measurement model is valid and reliable, we proceeded to conduct a structural model analysis. The results indicated that all the variables in our model had higher than necessary explanatory powers in terms of R-square values. The study results identified several important reward shemes. First of all, skill variety, task importance, task identity, and automony were all found to have significant influences on the intrinsic motivation of creating UCC contents. Also, the relationship with other users was found to have strong influences upon both intrinsic and extrinsic motivation. Finally, the opportunity to get recognition for their UCC work was found to have a significant impact on the extrinsic motivation of UCC users. However, different from our expectation, monetary compensation was found not to have a significant impact on the extrinsic motivation. It was also found that commitment was an important mediating factor in UCC environment between motivation and content creativity. A more fully mediating model was found to have the highest explanation power compared to no-mediation or partially mediated models. This paper ends with implications of the study results. First, from the theoretical perspective this study proposes and empirically validates the commitment as an important mediating factor between motivation and content creativity. This result reflects the characteristics of online environment in which the UCC creation activities occur voluntarily. Second, from the practical perspective this study proposes several concrete reward factors that are germane to the UCC environment, and their effectiveness to the content creativity is estimated. In addition to the quantitive results of relative importance of the reward factrs, this study also proposes concrete ways to provide the rewards in the UCC environment based on the FGI data that are collected after our participants finish asnwering survey questions. Finally, from the methodological perspective, this study suggests and implements a way to measure the UCC content creativity independently from the content generators' creativity, which can be used later by future research on UCC creativity. In sum, this study proposes and validates important reward features and their relations to the motivation, commitment, and the content creativity in UCC environment, which is believed to be one of the most important factors for the success of UCC and Web 2.0. As such, this study can provide significant theoretical as well as practical bases for fostering creativity in UCC contents.

PRC Maritime Operational Capability and the Task for the ROK Military (중국군의 해양작전능력과 한국군의 과제)

  • Kim, Min-Seok
    • Strategy21
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    • s.33
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    • pp.65-112
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    • 2014
  • Recent trends show that the PRC has stepped aside its "army-centered approach" and placed greater emphasis on its Navy and Air Force for a wider range of operations, thereby reducing its ground force and harnessing its economic power and military technology into naval development. A quantitative growth of the PLA Navy itself is no surprise as this is not a recent phenomenon. Now is the time to pay closer attention to the level of PRC naval force's performance and the extent of its warfighting capacity in the maritime domain. It is also worth asking what China can do with its widening naval power foundation. In short, it is time to delve into several possible scenarios I which the PRC poses a real threat. With this in mind, in Section Two the paper seeks to observe the construction progress of PRC's naval power and its future prospects up to the year 2020, and categorize time frame according to its major force improvement trends. By analyzing qualitative improvements made over time, such as the scale of investment and the number of ships compared to increase in displacement (tonnage), this paper attempts to identify salient features in the construction of naval power. Chapter Three sets out performance evaluation on each type of PRC naval ships as well as capabilities of the Navy, Air Force, the Second Artillery (i.e., strategic missile forces) and satellites that could support maritime warfare. Finall, the concluding chapter estimates the PRC's maritime warfighting capability as anticipated in respective conflict scenarios, and considers its impact on the Korean Peninsula and proposes the directions ROK should steer in response. First of all, since the 1980s the PRC navy has undergone transitions as the focus of its military strategic outlook shifted from ground warfare to maritime warfare, and within 30 years of its effort to construct naval power while greatly reducing the size of its ground forces, the PRC has succeeded in building its naval power next to the U.S.'s in the world in terms of number, with acquisition of an aircraft carrier, Chinese-version of the Aegis, submarines and so on. The PRC also enjoys great potentials to qualitatively develop its forces such as indigenous aircraft carriers, next-generation strategic submarines, next-generation destroyers and so forth, which is possible because the PRC has accumulated its independent production capabilities in the process of its 30-year-long efforts. Secondly, one could argue that ROK still has its chances of coping with the PRC in naval power since, despite its continuous efforts, many estimate that the PRC naval force is roughly ten or more years behind that of superpowers such as the U.S., on areas including radar detection capability, EW capability, C4I and data-link systems, doctrines on force employment as well as tactics, and such gap cannot be easily overcome. The most probable scenarios involving the PRC in sea areas surrounding the Korean Peninsula are: first, upon the outbreak of war in the peninsula, the PRC may pursue military intervention through sea, thereby undermining efforts of the ROK-U.S. combined operations; second, ROK-PRC or PRC-Japan conflicts over maritime jurisdiction or ownership over the Senkaku/Diaoyu islands could inflict damage to ROK territorial sovereignty or economic gains. The PRC would likely attempt to resolve the conflict employing blitzkrieg tactics before U.S. forces arrive on the scene, while at the same time delaying and denying access of the incoming U.S. forces. If this proves unattainable, the PRC could take a course of action adopting "long-term attrition warfare," thus weakening its enemy's sustainability. All in all, thiss paper makes three proposals on how the ROK should respond. First, modern warfare as well as the emergent future warfare demonstrates that the center stage of battle is no longer the domestic territory, but rather further away into the sea and space. In this respect, the ROKN should take advantage of the distinct feature of battle space on the peninsula, which is surrounded by the seas, and obtain capabilities to intercept more than 50 percent of the enemy's ballistic missiles, including those of North Korea. In tandem with this capacity, employment of a large scale of UAV/F Carrier for Kill Chain operations should enhance effectiveness. This is because conditions are more favorable to defend from sea, on matters concerning accuracy rates against enemy targets, minimized threat of friendly damage, and cost effectiveness. Second, to maintain readiness for a North Korean crisis where timely deployment of US forces is not possible, the ROKN ought to obtain capabilities to hold the enemy attack at bay while deterring PRC naval intervention. It is also argued that ROKN should strengthen its power so as to protect national interests in the seas surrounding the peninsula without support from the USN, should ROK-PRC or ROK-Japan conflict arise concerning maritime jurisprudence. Third, the ROK should fortify infrastructures for independent construction of naval power and expand its R&D efforts, and for this purpose, the ROK should make the most of the advantages stemming from the ROK-U.S. alliance inducing active support from the United States. The rationale behind this argument is that while it is strategically effective to rely on alliance or jump on the bandwagon, the ultimate goal is always to acquire an independent response capability as much as possible.

A Study on the Problem Analysis of Designation and Management of the Zone of Urban Nature Park (도시자연공원구역 지정 및 관리상의 문제점 분석)

  • Lee, Jeoung-Suk;Cho, Se-Hwan
    • Journal of the Korean Institute of Landscape Architecture
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    • v.39 no.3
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    • pp.98-106
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    • 2011
  • This study was performed with the purpose of providing basic data for the improvement of zoning regulations of urban nature park by analyzing the present problem which occurred during last 6 years from the year of 2005 when the program was introduced for the first time. The study was processed first by the analysis of the cases of problems evoked by citizens, second the other problems was delineated by interviews of officials, at last the validity of all of the problems was verified by a group of professionals through delphi method. The results can be summarized as follows. 1. In relation to the designation and management of urban national park areas, designation criteria, designation process, maintenance, laws and regulations and 20 other items were found to be problematic. After Delphi method, 5 items were removed and 2 added. The results showed that there were 17 problematic items in total. 2. Regarding the problem of criteria for designation, which are, lack of priority(weights), lack of objectivity due to the difficulty to use quantitative evaluation method, incompatibility for contaminated land environmental impact assessment, incompatibility of land suitability assessment, lack of detailed field survey standards, lack of national park area standards, and 6 other items. 3. Regarding the problem of designation process, which are, the occurrence of civil appeals for designating a new national park, the needs of feasibility study on the urban national park areas constructed before urban national park guidelines came out, lack of a comprehensive review of the boundaries set when determining national park area management plan, poor temporal and financial conditions for an accurate field survey, and 4 other items. 4. Regarding the problem of maintenance management, which are, lack of management system in each space, lack of effectiveness of Urban Nature Park Area Management Plan among master plans for park and green areas, the occurrence of dual managers due to dual natures such as purpose area and city park, lack of professional manpower to manage park areas, and 4 other items. 5. Regarding the problems of regulation guidelines, which are, lack of separate urban park area management plan, incompatibility of the permitted facilities in the park to the park area standards, lack of feasibility study on urban park areas, and 3 other items.

Factors Affecting Wet-Paddy Threshing Performance (탈곡기의 제작동요인이 벼의생탈곡성능에 미치는 영향)

  • 남상일;정창주;류관희
    • Journal of Biosystems Engineering
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    • v.5 no.1
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    • pp.1-14
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    • 1980
  • Threshing operation may be one of the most important processes in the paddy post-production system as far as the grain loss and labor requirement are concerned . head-feeding type threshers commercially available now in Korea originally were developed for threshing dry paddy in the range of 15 to 17 % in wet basis. However, threshing wet-paddy with the grain moisture content above 20 % has been strongly recommended, especially for new high-yielding Indica -type varieties ; (1) to reduce high grain loss incurred due to the handling operations, and (2) to prevent the quantitative and qualitative loss of milled -rice when unthreshed grains are rewetted due to the rainfall. The objective of this study were to investigate the adaptability of both a head-feeding type thresher and a throw-in type thresher to wet-paddy , and to find out the possiblilities of improving the components of these threshers threshing. Four varieties, Suweon 264 and Milyang 24 as Tongil sister line varieties, minehikari and Jinhueng as Japonica-type varieties, were used at the different levels of the moisture content of grains. Both the feed rate and the cylinder speed were varied for each material and each machine. The thresher output quality , composition of tailing return, and separating loss were analyzed from the sampels taken at each treatment. A separate experiment for measurement opf the power requirement of the head-feeding type thresher was also performed. The results are summarized as follows : 1. There was a difference in the thresher output quality between rice varieties. In case of wet-paddy threshing at 550 rpm , grains with branchlet and torn heads for the Suweon 264 were 12 % and 7 % of the total output in weight, respectively, and for the Minehikari 4.5 % and 2 % respectively. In case of dry paddy threshing , those for the Suweon 264 were 8 % and 5% , and for the Minehikari 4% and 1% respectively. However, those for the Milyang 23 , which is highly susceptable to shattering, were much lower with 1 % and 0.5% respectively, regardless of the moisture content of the paddy. Therefore, it is desirable to breed rice varieties of the same physical properties as well as to improve a thresher adaptable to all the varieties. Torn heads, which increased with the moisture content of rall the varieties except the Milyang 23 , decreased as the cylinder speed increased, but grains with branchlet didnt decrease. The damaged kernels increased with the cylinder speed. 3. The thresher output quality was not affected much by the feed rate. But grains with branchlet and torn heads increased slightly with the feed rate for the head-feeding type thresher since higher resistance lowered at the cylinder speed. 4. In order to reduce grains with branchlet and torn heads in wet-paddy threshing , it is desirable to improve the head-feeding type thresher by developing a new type of cylinder which to not give excess impact on kernels or a concave which has differenct sizes of holes at different locations along the cylinder. 5. For the head-feeding type thresher, there was a difference in separating loss between the varieties. At the cylinder speed of 600 rpm the separating losses for the Minehikari and the Suweon 264 were 1.2% and 0.6% respectively. The separating loss of the head-feeding type thresher was not affected by the moisture content of paddy while that of the Mini-aged thresher increased with the moisture content. 6. From the analysis of the tailings return , to appeared that the tailings return mechanism didn't function properly because lots of single grains and rubbishes were unnecessarily returned. 7. Adding a vibrating sieve to the head-feeding type thresher could increase the efficiency of separation. Consequently , the tailing return mechanism would function properly since unnecessary return could be educed greatly. 8. The power required for the head-feeding type thresher was not affected by the moisture content of paddy, but the average power increased linearly with the feed rate. The power also increased with the cylinder speed.

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Effect of Glucose Control, SDSCA and Quality of Life of D-chiro-inositol(DCI) in patients with type 2 diabetes: A Path Analysis (제2형 당뇨병 환자의 D-chiro-inositol의 혈당강하 효과와 당뇨 자가관리 및 삶의 질: 경로분석)

  • Kang, Young Mi;Kim, Hyun Jin;Lee, Tae-Yong;Ku, Bon-Jeong
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.10
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    • pp.243-253
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    • 2018
  • This study aimed to investigate the effects of DCI on glucose control, quality of life(SF-36 Version 2.0, Korean) and SDSCA(Summary of Diabetes Self-Care Activities) in patients with type 2 diabetes mellitus. A randomized, double-blind, placebo-controlled study was performed on 46 patients with HbA1c 7.0% taking triple anti-diabetic drug regimen who visited the department of Endocrinology and Metabolism in Chungnam National University Hospital between March 2015 and May 2016. As a result, DCI treatment in the intervention group resulted in significantly reduced HbA1c levels $8.75{\pm}0.79%$(baseline), $8.36{\pm}1.03%$(after 12weeks), and $8.65{\pm}0.81%$(after 24weeks). However, patients in the control group did not show any significant change. Interestingly, both DCI treatment group and the control group significantly showed improvements in SDSCA. Participants in the intervention group showed a small yet significant improvement in their only fasting blood glucose test in SDSCA and revealed significant increase in the quantitative levels of quality of life, from $73.05{\pm}16.85$ to $82.74{\pm}10.68$. By using pathway analysis, improvement of SDSCA scores(${\beta}=-0.505$, t=-2.743) was the most influential factor to the fasting blood glucose. The quality of life of patients with type 2 diabetes mellitus was affected by changes of SDSCA scores(${\beta}=0.411$, t=2.024) and fasting c-peptide(${\beta}=-0.445$, t=-2.668) in DCI treatment group. In conclusion, treatment of DCI effectively improved glucose control in patients with type 2 DM(HbA1c level>7.0%) after 12 weeks of treatment, although it had no impact on glucose control after 24 weeks of treatment. Improved glucose control may encourage diabetic patients to conduct self-care activities and improve the quality of life. Based on the present study, we suggest that diabetes self-management, as well as consideration of comprehensive laboratory findings, may be important factor in regulating the quality of life in type 2 DM patients.

Flipped Learning in Socioscientific Issues Instruction: Its Impact on Middle School Students' Key Competencies and Character Development as Citizens (플립러닝 기반 SSI 수업이 중학생의 과학기술 사회 시민으로서의 역량 및 인성 함양에 미치는 효과)

  • Park, Donghwa;Ko, Yeonjoo;Lee, Hyunju
    • Journal of The Korean Association For Science Education
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    • v.38 no.4
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    • pp.467-480
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    • 2018
  • This study aims to investigate how flipped learning-based socioscientific issue instruction (FL-SSI instruction) affected middle school students' key competencies and character development. Traditional classrooms are constrained in terms of time and resources for exploring the issues and making decision on SSI. To address these concerns, we designed and implemented an SSI instruction adopting flipped learning. Seventy-three 8th graders participated in an SSI program on four topics for over 12 class periods. Two questionnaires were used as a main data source to measure students' key competencies and character development before and after the SSI instruction. In addition, student responses and shared experience from focus group interviews after the instruction were collected and analyzed. The results indicate that the students significantly improved their key competencies and experienced character development after the SSI instruction. The students presented statistically significant improvement in the key competencies (i.e., collaboration, information and technology, critical thinking and problem-solving, and communication skills) and in two out of three factors in character and values as global citizens (social and moral compassion, and socio-scientific accountability). Interview data supports the quantitative results indicating that SSI instruction with a flipped learning strategy provided students in-depth and rich learning opportunities. The students responded that watching web-based videos prior to class enabled them to deeply understand the issue and actively engage in discussion and debate once class began. Furthermore, the resulting gains in available class time deriving from a flipped learning approach allowed the students to examine the issue from diverse perspectives.

Definition of Tumor Volume Based on 18F-Fludeoxyglucose Positron Emission Tomography in Radiation Therapy for Liver Metastases: An Relational Analysis Study between Image Parameters and Image Segmentation Methods (간 전이 암 환자의 18F-FDG PET 기반 종양 영역 정의: 영상 인자와 자동 영상 분할 기법 간의 관계분석)

  • Kim, Heejin;Park, Seungwoo;Jung, Haijo;Kim, Mi-Sook;Yoo, Hyung Jun;Ji, Young Hoon;Yi, Chul-Young;Kim, Kum Bae
    • Progress in Medical Physics
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    • v.24 no.2
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    • pp.99-107
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    • 2013
  • The surgical resection was occurred mainly in liver metastasis before the development of radiation therapy techniques. Recently, Radiation therapy is increased gradually due to the development of radiation dose delivery techniques. 18F-FDG PET image showed better sensitivity and specificity in liver metastasis detection. This image modality is important in the radiation treatment with planning CT for tumor delineation. In this study, we applied automatic image segmentation methods on PET image of liver metastasis and examined the impact of image factors on these methods. We selected the patients who were received the radiation therapy and 18F-FDG PET/CT in Korea Cancer Center Hospital from 2009 to 2012. Then, three kinds of image segmentation methods had been applied; The relative threshold method, the Gradient method and the region growing method. Based on these results, we performed statistical analysis in two directions. 1. comparison of GTV and image segmentation results. 2. performance of regression analysis for relation between image factor affecting image segmentation techniques. The mean volume of GTV was $60.9{\pm}65.9$ cc and the $GTV_{40%}$ was $22.43{\pm}35.27$ cc, and the $GTV_{50%}$ was $10.11{\pm}17.92$ cc, the $GTV_{RG}$ was $32.89{\pm}36.8$4 cc, the $GTV_{GD}$ was $30.34{\pm}35.77$ cc, respectively. The most similar segmentation method with the GTV result was the region growing method. For the quantitative analysis of the image factors which influenced on the region growing method, we used the standardized coefficient ${\beta}$, factors affecting the region growing method show GTV, $TumorSUV_{MAX/MIN}$, $SUV_{max}$, TBR in order. The result of the region growing (automatic segmentation) method showed the most similar result with the CT based GTV and the region growing method was affected by image factors. If we define the tumor volume by the auto image segmentation method which reflect the PET image parameters, more accurate and consistent tumor contouring can be done. And we can irradiate the optimized radiation dose to the cancer, ultimately.

Results of Radiotherapy for the Uterine Cervical Cancer (자궁경부암의 방사선치료성적)

  • Kim, Chul-Yong;Choi, Myung-Sun;Suh, Won-Hyuck
    • Radiation Oncology Journal
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    • v.6 no.1
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    • pp.63-73
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    • 1988
  • One hundred fifty-four patients with the carcinoma of the uterine cervix were studied retrospectively to assess the result and impact of treatment at Department of Radiation Oncology, Korea University, Hae-Wha Hospital from Feb 1981 through Dec. 1986. Prior to radiotherapy, the patients were evaluated and staged by recommendation of FIGO including physical examination, pelvic examination, cystoscopy, rectosigmoidoscopy, chest X-ray, IVP. Ba enema. Also, an additional pelvic CT scan was obtained for some of the patients. The patients were treated by radiotherapy alone or adjuvant postoperative irradiation; in case of radiation therapy only, whole pelvic irradiation was given with Co-60 teletherapy unit via AP and PA parallel opposing fields or 4-oblique fields, 180 cGy per day, 5 days per week and intracavitary insertion was performed. In satges Ia, Ib, and IIa with small primary lesion, external irradiation was initially given to pelvis up to $2,000\~3,000\;cGy/2frac{1}{2}\;-3frac{1}{2}$ weeks and then intracavitary insertion was performed using Fletcher-Mini-Declos Applicator with cesium-137 cources and followed by external irradiation of $1,000\~2,000\;cGy/1frac{1}{2}\;-2frac{1}{2}$weeks via AP and PA parallel opposing fields with midline shield to spare of bladder and rectum. However, if the primary lesion is large, external irradiation was given without midline shield. More than stages IIb, the patients were treated by external beam irradiation up to 5,400cGy/30f for 6 weeks via 4-oblique portals and at the dose of 5,040cGy/28f the field was cut 5cm from the top margin for spare of small bowel, and followed by intracavitary irradiation, If there was residual tumor an additional dose of $900\~l,200cGy/5\~7f$ was given to parametrium and/or residual tumor area. Total dose of radiation to A and B-point were as follows; A-point; In early stages, Ia, Ib, IIa; $8,000\~9,000$ B-point $5,000\~6,000 cGy$ A-point; In advanced stages IIb, IIIa, IIIb; $9,000\~10,000$ B-point $60,000\~7,000cGy$ The results were obtained and as fellows; 1 The patients distribution according to FIGO staging system were stage Ia 6, Ib 27, IIa 28, IIb 54, IIIa 12, IIIb 18, and stage IVa 9. 2. Value of CT scan were demonstration of cervix tumor mass, parametrial and pelvic side wall tumor spread, pelvic and inguinal lymph nodes metastases, and hydronephrosis. Three dimensional quantitative demonstration of tumor volume is also important in planning radiation therapy. Another advantage of CT scan was detection of recurrent tumor after radiation or surgery. 3. Local control rate of tumor according to the size was $91.3\%$ for less than 5cm in size and $44.6\%$ in tumor over 5cm (p<0.0068). 4. Thirty out of 50 recurrent sites has locoregional failures and 17 cases has distant metastases. And the para-aortic lymph nodes were the most common site for distant metastases. 5. The most common complication was temporal rectal bleeding which was controlled most by conservative management. However, 4 patients required for endoscopic cauterization. 6. The 5-year survival rates showed; stage la and Ib $95\%,\;stage\;IIa\;81\%\;stage\;lIb\;67\%,\;stage\;IIIa\;37.7\%,\;stage\;IIIb\;23\%$ and 3-year survival rate of stage IVa showed $11.6%$, retrospectively.

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